GitHub GraphQL API (https://docs.github.com/en/graphql) queries that can be executed via the explorer (https://docs.github.com/en/graphql/overview/explorer).

count-pull-requests-on-a-repo.graphql

query { 
    repository(owner: "softwarevidal", name: "arthur") {
      pullRequests(states: [OPEN]) {
        totalCount
      }
    }
}

last-20-merged-pull-requests.graphql

query { 
    repository(owner: "softwarevidal", name: "arthur") {
      pullRequests(last: 20, states: MERGED) { 
      	totalCount,
      	edges {
          node {
            id,
            number,
            title
            createdAt,
            updatedAt
          }
        }
    }
  }
}

pull-requests-timeline.graphql

query MergedPullRequests {
  repository(name: "pullpito", owner: "nicokosi") {
    pullRequests(last: 30) {
      edges {
        node {
          title
          createdAt
          createdBy: author {
            login
          }
          timelineItems(last: 10, since: "2017-01-01T10:28:04Z") {
            edges {
              node {
                ... on MergedEvent {
                  mergedAt: createdAt
                  mergedBy: actor {
                    login
                  }
                }
                ... on ClosedEvent {
                  closedAt: createdAt
                  closedBy: actor {
                    login
                  }
                }
                ... on IssueComment {
                  commentedBy: author {
                    login
                  }
                  comment: bodyText
                  publishedAt
                }
              }
            }
          }
        }
      }
    }
  }
}

pull-requests-timelines.graphql

{
  repository(owner: "docker", name: "docker-ce") {
    pullRequests(last: 10) {
      edges {
        node {
          createdAt
          author {
            login
          }
          number
          timelineItems(last: 10, since: "2020-02-01T10:28:04Z") {
            edges {
              node {
                ... on Comment {
                  __typename
                  createdAt
                  author {
                    login
                  }
                }
                ... on MergedEvent {
                  __typename
                  createdAt
                  __typename
                  actor {
                    login
                  }
                }
                ... on ClosedEvent {
                  __typename
                  createdAt
                  actor {
                    login
                  }
                }
                ... on PullRequestReview {
                  __typename
                  createdAt
                }
              }
            }
          }
        }
      }
    }
  }
}

repo-metadata.graphql

{
  repository(owner: "softwarevidal", name: "arthur") {
    repositoryTopics(last: 20) {
      nodes {
        topic {
          name
        }
      }
    },
    description,
    collaborators {
      edges {
        node {
          login
        }
      }
    },
  }
}

repo-names-from-org-with-topic.graphql

{
  search(type: REPOSITORY, query: "org:softwarevidal topic:sentinel", first: 100) {
    repos: edges {
      repo: node {
        ... on Repository {
          name
        }
      }
    }
  }
}